Quote:
Originally Posted by Zetr0
okay, so I managed to find a source of Intel P21010-08 chips
however I am even more confused as the intel P21010-08 thats populated in the picture is in fact a 256x1 NMOS Dymanic RAM DRAM chips, and not a 256x4 DRAM chip as the site suggest it should be.
Now I might be a little off with my calulation as the picture of 256x1 but depending on how the bank is setup I think I have manage to confuse myself.
If each chip is 256Kx1 - looking at the banks (in groups of 4 chips)
Bank 1 (256K x 4 bit) = 128KB ---------- ( 1Mx1)
Bank 2 (256K x 8 bit) = 256KB ---------- ( 1Mx2)
Bank 3 (256K x 12 bit) = 384KB --------- ( 1Mx3)
Bank 4 (256K x 16 bit) = 512KB --------- ( 1Mx4)
with 256x4 - each bank would be 1Mx4 (0.5mb) giving you 2Mx16 with 4 banks fully populated = which is 2MB ?
Bank 1 (1M x 4 bit wide ) = 0.5MB ---------- ( 256x16)
Bank 2 (1M x 8 bit wide ) = 1.0MB ---------- ( 512x16)
Bank 3 (1M x 12 bit wide) = 1.5MB ---------- ( 768x16)
Bank 4 (1M x 16 bit wide) = 2.0MB ---------- ( 1Mx16)
now the nubers are little out in my head because to use 256x1 would require the card to be able auto config its own ram and access it differently compared to 256x4 - so can anyone confirm the above rambling ?
1. Have I got my math wrong (yes it is a sunday)
2. Have amiga.resource been given the wrong info?
3. Did some one decide to put some random 256x1 intel DIP DRAM's for just the photo shoot?
4. has anyone got a picture of this card with 2MB installed?
thanks for reading =)
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The P21010 is a 1M x 1, not 256K x 1
http://www.datasheetarchive.com/P21010-datasheet.html